Ionization chambers for a flowing medium to be ionized are, of course, known and generally comprise an elongated cylindrical housing traversed longitudinally by the gas stream and, therefore, having an inlet end for the gas stream to be ionized, an outlet end for the gas stream to be discharged, and, within this chamber an anode and a cathode generally connected to a direct current source.
The anode in a conventional ionization chamber of this type generally is a wire extending centrally through this chamber in the longitudinal direction, i.e. is usually disposed along the axis of the chamber and can be a rod if desired. The cathode, however, is usually a cylindrical shell which is coaxial with the anode and can be formed by the housing wall itself. In either case the medium flows parallel to the anode and the cathode (See Holleman, Wiberg: "Lehrbuch der anorganischen Chemie", Berlin, 1964, page 178).
Ionization of a flowing medium may be practiced for a variety of reasons and hence the discussion here will concentrate on atmospheric air or pharmaceutical grade oxygen as the flowing medium to be ionized. When room air, oxygen-enriched air or even pure oxygen is ionized, it contributes to a variety of therapeutic processes and also in general, to the well-being of persons subject to the ionized oxygen. Many investigations have shown that the ion concentration of room air has a significant effect upon the emotional states of individuals present in the room and, in general, with elevated ion concentrations, individuals feel healthier, more active, and for the most part, satisfied and happy. Excessively low ion concentrations, however, contribute to a general feeling of malaise (see Lueger: "LEXIKON DER TECHNIK", Band 6, "Lexikon der Energietechnik und Kraftmaschinen" DVA, Stuttgart, 1965, pages 90 and 91, keyword "Behaglichkeit (Wohlbefinden)").
Apart from the use of ionization devices in personnel-occupied rooms to impart a general feeling of well-being, a number of therapeutic uses for highly ionized gaseous oxygen have been developed, and indeed, respiration therapy using gaseous oxygen with ionization is of considerable significance for various therapeutic treatments.
Ionization of gaseous oxygen utilizing the ionization chamber described above can give ion concentrations up to about 15,000 ions/cm.sup.3, However, simultaneously with the generation of such ions, there is a significant production of ozone (O.sub.3). This is a crucial disadvantage, especially for medicinal applications of ionized oxygen or air, because ozone in significant concentrations has a corrosive effect on the respiratory organs.